title: Vascular compliance limits during sleep deprivation and recovery sleep.
abstract: OBJECTIVE
  Our previous studies showed that evoked hemodynamic responses are smaller during wake compared to sleep; suggesting neural activity is associated with vascular expansion and decreased compliance. We explored whether prolonged activity during sleep deprivation may exacerbate vascular expansion and blunt hemodynamic responses.
  
  
  METHODS
  Evoked auditory responses were generated with periodic 65 dB speaker clicks over a 72-h period and measured with cortical electrodes. Evoked hemodynamic responses were measured simultaneously with optical techniques using three light-emitting diodes, and a photodiode.
  
  
  METHODS
  Animals were housed in separate 30×30×80 cm enclosures, tethered to a commutator system and maintained on a 12-h light/dark cycle. Food and water were available ad libitum.
  
  
  METHODS
  Seven adult female Sprague-Dawley rats.
  
  
  METHODS
  Following a 24-h baseline recording, sleep deprivation was initiated for 0 to 10 h by gentle handling, followed by a 24-h recovery sleep recording. Evoked electrical and hemodynamic responses were measured before, during, and after sleep deprivation.
  
  
  RESULTS
  Following deprivation, evoked hemodynamic amplitudes were blunted. Steady-state oxyhemoglobin concentration increased during deprivation and remained high during the initial recovery period before returning to baseline levels after approximately 9-h.
  
  
  CONCLUSIONS
  Sleep deprivation resulted in blood vessel expansion and decreased compliance while lower basal neural activity during recovery sleep may allow blood vessel compliance to recover. Chronic sleep restriction or sleep deprivation could push the vasculature to critical levels, limiting blood delivery, and leading to metabolic deficits with the potential for neural trauma.
authors.affiliation: Department of Veterinary and Comparative Anatomy, Pharmacology and Physiology, Washington State University, Pullman, WA.
authors.forename: Derrick J
authors.initials: DJ
authors.lastname: Phillips
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Schei
authors.forename: David M
authors.initials: DM
authors.lastname: Rector
mesh_terms: D000818:Animals; D001808:Blood Vessels / Q000502:physiology* / Q000503:physiopathology; D004569:Electroencephalography; D005072:Evoked Potentials, Auditory / Q000502:physiology; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D010108:Oxyhemoglobins / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D012890:Sleep / Q000502:physiology*; D012892:Sleep Deprivation / Q000503:physiopathology*
chemical_list: D010108:Oxyhemoglobins
keywords: Optical imaging; evoked response potentials; hemoglobin; metabolism; rat